Distributing valve



,1951 H. k. HSCHER ETAL 2,57 ,096

DISTRIBUTING VALVE Original Filed Dec. 13, 1945 SHEETS-SHEET 1 A ii 79@3 L 323 z WW4 1 IN VEN TORS Hon 4120 B. FISCHER BY JAMS 4. koaE/ersNov. 6, 1951 FISCHER ET AL 2,574,096

DISTRIBUTING VALVE Original Filed Dec. 15, 1945 2 SHEETSSHEET 2 59 IN VEN TORS HWY/7RD E. Flscnse JAMES 14. EOEEETS J9 WWZZ Patented Nov. 6,1951 DISTRIBUTING VALVE Howard B. Fischer and James A. Roberts, De-

troit, Mich., assignors to Chicago Pneumatic Tool Company, New York, N.Y., a corporation of New Jersey Original application December 13, 1943,Serial No. 514,068. Divided and this application July 26, 1946, SerialNo. 686,406

2 Claims. 1

This invention relates to a valve and more particularly to a fluidcontrol valve for regulating the flow of pressure fluid forreciprocating a piston associated with work engaging members in suchmachines as riveters, dimplers, punches, presses and similar apparatusoperating on a compression principle. This application is a division ofparent application, Serial No. 514,068, filed December 13, 1943 (nowabandoned).

An object of this invention is to provide a fluid control valve adaptedto be operated to cut off the supply of pressure fluid in one directionand instead cause the fluid to flow in the opposite direction to efiectstopping and reversal of a compression machine such as a riveter ordimpler.

Another object is to provide a fluid control valve whose reciprocatingmember is adapted to be moved by actuating means in cooperation withgravity and spring means.

Another object is to provide a valve adapted to reverse the stroke of apiston automatically upon a predetermined degree of approach between thecompression members of a riveting machine or the like.

Other objects and features of the invention will appear more clearlyfrom the following description taken in connection with the accompanyingdrawings and appended claims.

In the accompanying drawings:

Fig. 1 is a fragmentary view of the upper operating mechanism of ariveting or dimpling machine with the piston and cylinder chamber andthe speed control valve in section to disclose the interior constructionthereof;

Fig.2 is a cross-section along line 22 of Fig. 1, on a larger scale,illustrating particularly the solenoid operated valve;

Fig. 3 is a plan view, on a still larger scale, of the solenoid valvelever;

Fig. 4 is a side view, partly in section, of the solenoid valve lever;

Fig. 5 is a schematic diagram of the electric apparatus and connectionsshowing the parts in idle condition but ready for operation; and

Fig. 6 is a diagram similar to that shown in Fig. 5 showing the parts atthe end of the power stroke and immediately prior to the opening of thedeflection plate switch.

Still referring to the drawings, the cylinder chamber H (Fig. 1)contains a reciprocable piston l2 provided with a hollow piston rod l3extending slidably through a seal I4 in the front wall l5 of thecylinder, the forward end of the piston rod receiving a boss l6 formingan extension upon a. forked roller block H in which a 2 pair ofrotatable rollers [8 are mounted one above the other.

In order to actuate the piston just indicated, a pressure fluid port [9(Fig. 2) in the rear wall 2! of the cylinder is arranged to receivepressure fluid (such as compressed air) from a passage 22 in valvehousing 23 under control of valve 24, the fluid being introduced intothe valve housing 23 through a flexible tube (not shown, but indicatedat 64) connected to an appropriate source of pressure fluid. Within thevalve housing 23 the valve 24 has two spaced pairs of valve heads 25, 26mounted on a reciprocating valve stem 21, and providing four individualseating type valves, mounted in pairs, back-to-back. Valve heads 25, 26consist of soft rubber discs each of which is perforated to fit andclosely surround the valve stem 21. The discs of each pair abut eachother while the pairs of heads are separated by a spacer sleeve 28. Thelower disc 26 seats against a shoulder 29 on the valve stem. Near itslower end the valve stem has a cylindrical portion 3| slidable in abushing 32 firmly fixed on a sleeve 33. Said sleeve 33 is secured byengaging in a thread 34 in the valve housing 23 and extends downwardlyfrom said thread but is formed upon its upper end with a valve seat 35engaged by the lower surface of valve head 26. The sleeve 33 is centeredat its lower end by internally threaded ring 36 screwed on the sleeveand fitted into a large end bore 31 in the valve housing, ring 36serving to retain the inner ring 38 as well as appropriate packing 39above and below the same in compressed condition to prevent leakageabove sleeve 33.

In the upper portion of the valve housing 23 a sleeve 4| is screwed intothreads 42 and is locked in position in the housing by a lock nut 43. Anupper section 44 of the valve stem is slidably supported in sleeve 4|.Section 44 screws on to the upper end of stem section 21 and engages theupper face of rubber disc 25 to hold all four discs under adjustableaxial compression. Sleeve 4| has a valve seat 45 at its lower endadapted to be engaged by the upper surface of valve head 25 in raisedposition of the valve. Between the two valve heads is located a valveseat bushing 46 held rigidly in an intermediate bore 41 in the valvehousing, this bushing having an upper valve seat 48 engaged by the lowersurface of valve head 25 and a lower valve seat 49 adapted to be engagedby the upper face of the other valve head 26 in raised position of thevalve. It is thus evident that valve head 25 is movable from valve seat45 to seat 48 in valve chamber 5| while valve head 26 is correspondinglymovable therewith between valve seats 49 and 35 in valve chamber 52.Between these valve chambers and the bushing 46 is an annular connectingpassage 53 alternately closed by valve head 25 and by head 26 while aport 54 opening into said passage communicates with a duct 55 which isconnected to the front end of the cylinder chamber II in well understoodmanner.

The previously mentioned passage 22 communicates through ports 56 insleeve 4| with an upper annular valve passage 51, said passage 22 andpassage 5! connecting with a passage 58 which extends down in the valvehousing toward the lower end thereof and communicates through ports 59in the sleeve 33 and ring 38 with a lower annular valve chamber 68 insleeve 33. The valve chamber 5| communicates by way of a passage 6| withan exhaust chamber 62 in the housing immediately behind the rear wall 2|of the cylinder. On the other hand, the valve chamber 52 communicates byway of a port 63 with the pressure fluid passage 64 which is in directcommunication (not shown) with the pressure fluid supplied the flexibletube heretofore alluded to. In this connection it should be pointed outthat the embodiment herein is merely illustrative and that theconnections of the valve to the mechanism shown may vary. For example,valve chamber 5| could be connected to the source of pressure fluidinstead of to the exhaust, and vice versa, chamber 52 could be connectedto the exhaust instead of to the pressure supply.

The exhaust air flowing from the front piston chamber into exhaustchamber 62 passes through speed control valve 65 (Fig. 1) whichregulates piston velocity on power stroke. From the exhaust chamber itflows through mufller 66 to atmosphere. Valve 65 is of the screw typeand provides an adjustable restriction for the escaping air undercontrol of a manipulative wheel 61. The wheel 61 is supported in aflange on cylinder 68 while the valve seat is in the cylinder chamberThe purpose of this valve is to provide an accurate control for thevelocity of travel of the piston l2 during the power stroke. Turning theadjustment wheel counterclockwise increases the speed of the piston,while clockwise adjustment decreases the speed by further restrictingthe flow of exhaust from the front cylinder chamber to suit rivetingconditions.

The control valve 24 is raised and lowered in response to actuatingmeans such as an electromagnetic coil device or solenoid 69. Thesolenoid is supported on a frame 1| (Fig. 1) which is mounted on thecontrol valve housing 23 and secured thereto by bolts 12 (one beingshown in Fig. 2). The solenoid comprises a core 13 reciprocating in acoil 14 rigidly mounted upon frame II and connected to a terminal box15.

The reciprocal motion of the solenoid is transmitted to the controlvalve by means of a lever in the manner following. The upper valve stem44 is screw threaded for the reception of two spaced adjusting nuts 16and I1. Above nut TI the sides of the valve stem 44 are flattened to fita rectangular slot 18 in a lever 19 (see Figs. 1 to 4). The rear end ofthe lever has a hole 8| cooperating with a pivotal support on frame 1|.The front end has a forked portion 82 engaging a horizontal pin 83carried by solenoid core 13 whereby the reciprocating movement of thecore causes the lever to rock about its pivot.

. 4 Lever 19 seats on adjusting nut 11 and is held in contact therewithby a compression spring 84 (Fig. 2) which encircles valve stem 44 andwhich is interposed between the lever and the upper adjusting nut 16.The two adjustment nuts and the compression spring are effective totransmit motion from the valve lever to the control valve 24. The spring84 and nut 16 disposed above the lever 19 actuate the control valve onthe upward or power stroke, whereas on the return stroke the valve 24is'carried down with the lever in contact with the adjusting nut 11.Downward movement of the valve 24 is aided by a compression spring 85surrounding the lower end 3| of the valve stem and extending between ashoulder on sleeve member 33 and a collar 86 pinned to the valve stem.The purpose of the spring 84 is to prevent injury to the valve seats dueto the inertia of the solenoid core I3 and also to obviate the necessityof close adjustments.

Referring now to the electric control system of the invention, it isapparent that when the solenoid is energized, the core 13 will promptlyraise the control valve 24 to its upper limit position to engage the twovalve heads 25 and 26 thereof simultaneously against valve seats 45 and49 but when said solenoid is de-energized with incident extinction ofits magnetic field by cessation of current flow through the windingsthereof, the valve as promptly drops to its initial position with thevalve heads 25 and 26 engaging with the valve seats 48 and 35 to effectthe return stroke of the piston l2. The valve thus controls thedirection and flow of the pressure fluid to the machine by controllingthe inlet and exhaust ports and passages thereof as already indicatedabove.

The present invention includes means for automatically breaking thecircuit of the solenoid to cut off the current supply thereto andthereby de-energize the same when the compression member, as for examplethe rivet set, has been brought down to a predetermined position, as inthe case in which a head has been properly set upon the rivet, as willbe explained. When this occurs, the core 13 is of course released fromthe magnetic field of solenoid 69 by extinction of said field whichallows the spring 84 to add its eflect to the force of gravity and causethe valve 24 to quickly descend and engage both valve heads against thevalve seats 48 and 35. In this position of the valve, pressure fluidentering valve chamber 52 (Fig. 2) through port 63 from supply passage64 rises through passage 53 about the intermediate portion of the valvestem, then enters port 54 and proceeds through passage 55 into the frontportion of the cylinder chamber driving the piston toward the rear ofsaid chamber. In the meantime the pressure fluid initially contained inthe rear portion of the cylinder chamber escapes along the pathindicated by arrows in Fig. 2 through port I9, passage 22, by way ofport 56 and valve passage 5! about the valve stem down to valve chamber5| and thence through passage 6| into exhaust chamber 62 from which itfinally escapes to the atmosphere. In the up position of the valve,which it assumes upon the closing of the circuit of the solenoid, thepressure fluid entering at 64 advances through port 63, valve chamber52, annular chamber 68,

' ports 59, passage 58;ports 56, passage 22 and to port IS in the rearwall 2| of the cylinder entering therethrough into'the rear portion ofthe cylinder chamber to drive the piston forwardly. In the meantime, thepressure fluid initially contained in the forward portion of thecylinder chamber escapes through passage 55, port 54, chamber 53,chamber 5|, passage 6I to exhaust chamber 62 and thence to atmosphere.

The various electrical connections and instruments used, such asswitches and relays and the like, are illustrated in their details indiagrammatic form in Figs. 5 and 6. The first of these two diagrams(Fig. 5) shows the apparatus in initial condition after a main lineswitch III has been closed and the apparatus or system is ready foroperation; and in both figures the parts, either simplified or modifiedin form, none the less are indicated as far as feasible by the samereferences borne by the corresponding actual parts in the other figuresalready described.

In the cycle of operation, referring primarily to Figs. 5 and 6, theoperator first closesthe line switch III to prepare the apparatus forinitial operation. This connects the system to a source of electromotiveforce, diagrammatically indicated as a battery H2, and closes a circuitH3 extending from said source through the winding of a relay H4 andthrough a relay armature H5 and back contact (or break contact) H6 toground. When relay II4 becomes energized, its armature I I! moves intoengagement with a front contact (or make contact) H8 to connect thegrounded end of the relay winding H4, through armature I I1, frontcontact H8, and conductor H9 to a fixed contact member I20 of the stopswitch I2I. A movable contact member I22 of the stop switch iscontrolled by the end I23 of the stop switch lever I24 and is connectedto a fixed contact member I25 of switch I26 while the latter has themovable grounded contact member I2I corresponding to the microswitch 95controlled by the deflection switch trip lever 96, the upper arm 99 ofwhich makes contact with the end of said contact member.

With the system thus in condition for action (Fig. 5) and assuming thatthe switch I2I and the tools I28 and I29 are set properly for the workto be performed, the work piece generally indicated at I30 is providedwith a rivet I3I and placed between the rivetin tools. Then the operatorsteps on a treadle shown diagrammatically at I32 on the foot switch I33bringing the movable contact member I34 down into contact with agrounded fixed contact member I35 (Fig. 6) and thereby closes thecircuit I36 through relay I 31 and energizes said relay, immediatelyshifting armature II5 associated with the latter away from grounded backcontact II6 into active engagement with a front contact I38 alsoassociated with said relay. This operation of the armature II5 passescurrent to the solenoid 69 through conductor I39 from current source H2,the current continuing through conductor I, through contact members I38,H5, H1 and H8, through the further conductor I I9 to and through thestop switch I2I as well as trip switch I26 and finally to ground bycontact member I21. The solenoid 69 instantly raises the core I3 to itsupper operated position, raising the valve rod 44 and allowing pressurefluid to actuate the piston forwardly as previously described.

The forward movement of the piston I2 naturally causes the forward endor roller block II on the piston rod I3 to be driven forward likewise,the rollers I8 causing the cam lever I42 to be depressed, said lever inturn forcing plunger I43 down by means of cam I44 thereby forcing toolI29 down on rivet I3I mushrooming or setting the same to form a headupon the work piece I30. Should the upper roller I8 for any reason bedriven beyond its normal forward limit, it will make contact with switchlever I24 and cause the upper end I23 thereof to push movable contactmember I22 of stop switch I2I away from fixed contact member I20 thusopenin the circuit and instantly destroying the magnetic field of thesolenoid 69 and allowing the force of gravity assisted by the spring tobring valve 24 down to cut oil the supply of pressure fluid to the rearportion of cylinder member I I. When the piston travels toward the frontof the machine, the fiuid initially present in the front portion of thecylinder chamber is exhausted through passage 55, port 54, valve chamber5I, silencer 66, and Speed control valve 65 to atmosphere.

In normal operation the setting of the rivet resulting in the productionof a head virtually constitutes a squeezing action, imposing anexpanding strain on yoke 9I, but this operation when the head is fullyset gradually increases the expandin strain imposed on the jaws of saidyoke, and as already stated, definitely tends to separate these jaws toa measurable degree as indicated by the broken line at I03 (Fig. 6) incontrast with the relative unstrained position indicated by full lineI04. The relative change in position of the jaws raises the pivot 91fixed on jaw 94 while the lever actuating block I02 on the end 93 of thedeflection plate arm remains unchanged in position, the immediate resultbeing that the rising pivot 91 will cause the deflection switch triplever 96 to swing counterclockwise as viewed in said Fig. 6 because theshort arm 98 of the same lever is simultaneously prevented by the blockI02 on the deflection plate from following the upward movement of thepivot. The upper arm 99 of the lever is thus caused to operate switchmember and break contact thereof with contact member I25 opening thesolenoid circuit and causing the control valve 24 to cut off the supplyof pressure fluid to the rear of the cylinder and stop the forwardtravel of the piston and consequently also stop the downward travel ofthe rivet set I29.

During this operation the deflection trip switch lever 96 is shifted inposition about pivot 91 from that indicated in broken lines in Fig. 6 tothe operated position shown in full lines, the expansion of the jaws 89,94 of the yoke 9I causin the movement of the switch lever which is shownin the full lines at 99 in contrast with the normal free and unstrainedposition indicated by the broken line I05. It is of course understoodthat such expansion of the yoke with consequent operation of the switchlever and switch occurs at the moment when the rivet head is set to theintended degree, the adjustment for such setting being effected by meansof a knob (not shown) controlling the latitude of operation of the tripswitch at the front end of the machine.

From the electrical standpoint modifications are also feasible. Forexample, while certain of the contacts of the apparatus arediagrammatically indicated as grounded, they could well beinterconnected by means of conductors, and it is likewise true thatwhile several of the main contacts involved in the electrical controland operation of the system become effective by opening and breakingassociated circuits, such contacts and circuits can readily be arrangedto operate by said contacts normally being open and during operationclosing the circuits, instead. Moreover, the electric circuit could bedispensed with entirely and the motion of yoke deflection transmitted toa balanced control valve through the medium of a toggle multiplyingmechanism by purely mechanical means.

To those skilled in the art it is easily seen that the machine may beused not only for riveting and setting grommets and the like but may asreadily be used for dimpling sheet metal, although such use has not beenspecifically described herein, inasmuch as a mere change of tools andadjustments is required for such dimpling operation.

What is claimed is:

1. A distributing valve comprising a valve housing having an inlet andexhaust for pressure fluid and having front and rear passages forcommunicating with corresponding ends of a piston chamber, two pairs ofcoaxial annular valve seats supported in said housing, a reciprocablevalve stem axially aligned and having two pairs of annular valve heads,one pair of heads being engageable with one pair of seats when the valvestem is in a first position to connect the front passage to the inletand the rear passage to the exhaust. the other pair of heads beingengageable' with the other pair of seats when the valve stem is.

in a second position to connect the rear passage to inlet and the frontpassage to exhaust, yieldable means to maintain the valve stem in firstposition, actuating means having a movable element, a lever pivotallyconnected to the movable element at one end and having a fulcrum at theother end, said lever being slotted to receive the valve stem, adjustingmeans to vary the relative position of the lever with respect the valvestem, and resilient means interposed between the lever and the adjustingmeans to dampen transmission of shocks to the valve stem, all being soarranged to effect movement of said valve stem to second position whenthe actuating means is activated.

2. A distributing valve according to claim 1 wherein the adjusting meanscomprises movable members such as nut means.

HOWARD R. FISCHER. JAMES A. ROBERTS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 691,692 Zweigbergk Jan. 21, 19021,921,092 Newton Aug. 8, 1933 2,139,064 Beattie Dec. 6, 1938 2,194,782Baad Mar. 26, 1940 2,300,263 McLeod Oct. 27, 1942 2,313,843 Shaft Mar.16, 1943 2,321,079 Greenwald June 8, 1943 2,340,817 Hurst Feb. 1, 19442,354,841 Shafi Aug. 1, 1944 2,374,593 Ernst Apr. 24, 1945

